Reconstruction of the (001) Surface of Si from Molecular Dynamics

Abstract

The device applications of gallium arsenide and related Ill-V compound and alloy semiconductors are reviewed.A range of electronic devices is described, and the current state of the art performance is indicated for each type of device.The devices which will be described are: transferred electron devices -as oscillators up to 200 GHz, GaAs MESFETs -the workhorse microwave solid state device, some monolithic microwave integrated circuit /MMIC/, and heterojunction devices.The use of molecular beam epitaxy MBE to grow I l l -V s e m i c o n d u c t o r s w i t h g r e a t c o n t r o l o v e r t h e d o p i n g , m o l e f r a c t i o n o f t h e constituents and the thickness of the epilayer has permitted the construction of devices with atomically abrupt interfaces between regions of different doping and alloy.The electronic devices which make use of such abrupt heter o -j u n c t i o n s i n c l u d e : h i g h e l e c t r o n m o b i l i t y t r a n s i s t o r s , h e t e r o j u n c t i o n b i p o l a r transistor, and laser diodes.A number of novel devices based on multiple barrier and quantum well structures is also described, including Resonant Tunneling Devices.